Digital camera and printing system

ABSTRACT

With a digital camera  100 , a photographed image  31  is displayed on a liquid crystal display and the user selects a desired image and specifies print specifications of the number of print sheets, a print paper size, a print color mode, etc., then print image data is prepared. The prepared print image data is transmitted from the digital camera  100  to a color printer of an output unit. An image is printed at the color printer in accordance with the print image data.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] This invention relates to a digital camera and in particular to adigital camera capable of outputting image data directly to a printerand a printing system using the same.

[0003] 2. Related Art

[0004] In recent years, digital cameras (still-video cameras) have beendeveloped, sold, and finding spreading use.

[0005] The digital camera is configured to execute photoelectricconversion of image pickup light to provide image data, record the imagedata on a recording medium, and output the recorded image data to anexternal image processing system such as a personal computer (PC). Theexternal image processing system performs print image data preparationprocessing and outputs the prepared print image data to a printer forprinting or reproducing the picked-up image on paper.

[0006] Most digital cameras comprise each a liquid crystal display fordisplaying the image pickup result and the image data provided byphotoelectric conversion is compressed and recorded on a recordingmedium. To compress the image data, normally JPEG (Joint PhotographicExpert Group) standard is applied.

[0007] To select an image on a PC, a number of thumbnail imagescompressed in JPEG (described later) are previously input and displayedon a monitor. The picked-up image data corresponding to a selectedthumbnail image is input from the digital camera and is decompressed,then displayed on the monitor. When the user recognizes it, color printimage data preparation processing is performed and the image is printedat a printer connected to the PC.

[0008] The thumbnail image is a reduced image used for the user toselect a desired image out of the input image data on a PC, etc. Forexample, assuming that the size of 1-frame image data is 680×480 pixels,the corresponding thumbnail image is reduced by thinning out the data toabout 80×60 pixels; the thumbnail images are recorded on a recordingmedium of the digital camera in a one-to-one correspondence with normalpicked-up images.

[0009] When color print image data preparation processing is performed,print image data preparation processing is performed by programs on thePC to reproduce or print a color image (video) with high accuracy andbit map data is prepared for each print color required for drawing andis given to a printer together with a control signal for performing thecolor image reproduction operation on recording paper.

[0010] A color print ink jet printer capable of printing a high-qualityimage like a picture or a photo is developed and sold as a colorprinter.

[0011] The above-mentioned print image data preparation processingprograms are contained in a program group called a printer driver in adata processing module 210 as shown in FIG. 11. A printer driver 220normally comprises three modules of rasterizer, color correction, andhalftone as means for obtaining binary data.

[0012] However, usually the PC comprises a large number of applicationprograms other than image (video) print processing because of generalversatility. The application programs and the above-mentioned printerdriver operate under the control of Windows, MS-DOS, etc., (PC operatingsystem (OS) manufactured by Microsoft Corporation).

[0013] Therefore, to perform image print processing, the user needs toenter commands as specified by the OS for reading the print processingapplication program and the printer driver into PC internal memory froma storage unit storing them (for example, magnetic disk) and placingthem in an executable state. However, it takes time (so-called overheadtime) to enter commands and read the print processing applicationprogram and the printer driver; the overhead time requires severalminutes at the shortest, thus it takes time to start.

[0014] Although PCs are finding remarkable spreading use, many problemsremain to be solved for users to know how to actually handle PCs; it isalso pointed out that most persons who have PCs cannot master them. Ifthey attempt to install the image (video) print processing applicationprogram and the printer driver, they may find it difficult to installthe software or may not understand how to enter the commands.

[0015] The need for using an expensive PC only for the purpose ofprinting picked-up images involves remarkable impairment of user'sconvenience.

[0016] Examining demands for simplifying the print processing operationand reducing the overhead time almost to zero from the aspect of thedigital camera, preferably, for example, image data can be output fromthe digital camera directly to a printer without intervention of a PCand a desired picked-up image can be printed on a desired number ofprint sheets in a desired paper size and print color mode. Morepreferably, an external unit to which image data is to be transmittedincluding a printer can be specified.

SUMMARY OF THE INVENTION

[0017] It is therefore an object of the invention to provide a digitalcamera having capabilities of outputting image data directly to anexternal system and printing a desired image under desired printspecifications of the number of print sheets, paper size, print colormode, etc. It is another object of the invention to provide a printingsystem using the digital camera.

[0018] According to one aspect of the invention, there is provided adigital camera for executing photoelectric conversion of image pickuplight and then recording the conversion result as image data, thedigital camera comprising a display section for displaying an image, arecording medium for recording the image data, image data selectionmeans for selecting desired image data out of the recording medium, andoutput method specification means for outputting the selected image datato an external system under predetermined output specifications. Theimage data selection means reads the image data for each frame and addsan index to the image data for display on the display section.

[0019] According to another aspect of the invention, there is provided adigital camera for executing photoelectric conversion of image pickuplight and then recording the conversion result as image data andthumbnail image data of the image data, the digital camera comprising adisplay section for displaying an image, a recording medium forrecording the image data and the thumbnail image data, thumbnail imagedisplay means for reading the thumbnail image data from the recordingmedium and displaying thumbnail images on the display section, imagedata selection means for selecting one of the displayed thumbnailimages, thereby selecting desired image data corresponding thereto, andoutput method specification means for outputting the selected image datato an external system under predetermined output specifications. Thethumbnail image display means enlarges and displays the thumbnail image.

[0020] According to another aspect of the invention, there is provided adigital camera for executing photoelectric conversion of image pickuplight and then recording the conversion result as image data andthumbnail image data of the image data, the digital camera comprising adisplay section for displaying an image, a recording medium forrecording the image data and the thumbnail image data, thumbnail imageprint means for printing out the thumbnail image data recorded on therecording medium at an external printer, thumbnail image display meansfor reading the thumbnail image data from the recording medium anddisplaying thumbnail images on the display section, image data selectionmeans for selecting one of the displayed thumbnail images based on theprinted thumbnail images, thereby selecting desired image datacorresponding thereto, and output method specification means foroutputting the selected image data to an external system underpredetermined output specifications. The thumbnail image print meansadds an index to each thumbnail image data piece and outputs to theexternal printer and the index of one of the indexed thumbnail imagesprinted is specified, whereby the image data selection means selectsdesired image data corresponding thereto.

[0021] With the digital cameras according to the three aspects of theinvention, the external system is a color printer and the predeterminedoutput specifications contain at least one of the number of printcopies, a print paper size, and a print color mode for printing theimage data. The print color mode is full color, single color, ormonochrome. The external system contains a printer or a facsimile or animage processing system connected by a communication line.

[0022] A printing system provided according to the invention comprisesany of the three types of digital cameras described above and a colorprinter as an external system.

BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In the accompanying drawings:

[0024]FIG. 1 is a block diagram to show a configuration example of adigital camera of the invention;

[0025]FIG. 2 is a block diagram to show a configuration example ofcontrol means stored in ROM;

[0026]FIG. 3 is a block diagram to show a configuration example of imageselection means;

[0027]FIG. 4 is a block diagram to show the relationship among imageselection means, print image data preparation programs, and controlmeans;

[0028]FIG. 5 is a flowchart to show brief operation of a controlsection;

[0029]FIG. 6 is a block diagram to show a configuration example ofoutput method specification means;

[0030]FIG. 7 is an example of a rear part view of the digital camera;

[0031]FIG. 8 is a flowchart to show an operation example from imageselection to print image data preparation;

[0032]FIG. 9 is a flowchart to show another operation example from imageselection to print image data preparation;

[0033]FIG. 10 is a flowchart to show another operation example fromimage selection to print image data preparation; and

[0034]FIG. 11 is a block diagram to show an example of print image datapreparation programs used to prepare print data on a personal computer.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0035]FIG. 1 is a block diagram to show a configuration example of adigital camera of the invention.

[0036] As shown in FIG. 1a, a digital camera 100 comprises an opticalsystem consisting of a lens, an iris mechanism, etc., through whichreflected light from an image to be photographed is incident on a CCD 2,the CCD 2 for converting image pickup light from the optical system 1into an electric signal, a signal processing section 3 for processingthe signal from the CCD 2 and outputting the processed signal to a framememory 6 as multiple-valued (R, G, B) raster data (image data), acontrol section 4 for controlling the operation of the signal processingsection 3, frame memories 6 and 6′, a signal processing section 7, and arecording medium control section 8, image processing, imagecompression/decompression processing, etc., input means 5 for inputtinga command entered by the user operating a switch, etc., converting thecommand into a digital signal, and feeding the digital signal into thecontrol section 4, the signal processing section 7 for converting R, G,B raster data in the frame memory into brightness component Y and colordifference components U and V, compressing the data in JPEG, andperforming reduction processing for preparing a thumbnail image, arecording medium control section 8 for receiving output of the signalprocessing section 7 and controlling writing of the image datacompressed in JPEG, which will be hereinafter referred to as JPEG imagedata, and thumbnail image data into predetermined locations of arecording medium 9 or an expanded recording medium 10, read of therecorded JPEG image data therefrom, etc., the recording medium 9 andexpanded recording medium 10 for storing image data, an interface 11used to transfer data to and from an external system, display means 15of a LED lamp, etc., for displaying the switch state, functionalspecifications, etc., and display means 16 made of a liquid crystaldisplay, etc., for displaying a photographed image or an object to bepicked up.

[0037] The frame memory 6 normally is used as an image display memory ofthe liquid crystal display 16 and image data is expanded in bit mapimage. The frame memory 6′ normally is used as a menu display memory ofthe liquid crystal display 16. At the display time on the liquid crystaldisplay 16, the contents of the frame memories 6 and 6′ are superimposedon each other on the display.

[0038] The recording medium 9 is made of a 4-MB flash memory fixed inthe camera 100. It can be configured to record not only image data, butalso programs, etc. Compact flash (trademark of Sun Disk) having acapacity of 4-40 MB is used as the expanded recording medium 10 in theembodiment.

[0039] A serial interface is used as the interface 11 in the embodimentto receive a program sent from a computer such as a PC 200, transmitimage data to the PC 200, send image data via a modem 150 to acommunication line 160, etc., and transmit print image data to a printer240 or a facsimile machine.

[0040]FIG. 1b shows the configuration of the control section 4 whichconsists of a CPU 41, a RAM 42, and a ROM 43. The ROM 43 stores controlmeans 430 made up of programs required for operation control of thedigital camera 100 and data processing in the digital camera such asdata compression processing (FIG. 2).

[0041] Print data preparation programs including a printer driver may bestored in the ROM 43. Alternatively, they can also be read from anexternal recording medium such as magnetic disk, CD-ROM, or a memorycard into the recording medium 9 or the expanded recording medium 10 andbe read therefrom for execution at a desired time.

[0042]FIG. 2 is a block diagram to show a configuration example of thecontrol means 430 stored in the ROM 43. The control means 430 consistsof means required for operation control of the digital camera 100, imagedata processing means required in the process of storing image data suchas compression of image data, and means for decompressing compressedimage data and preparing print data. Normally, the means are made ofprograms.

[0043] The control means 430 comprises a control system 431, inputcommand determination means 432, an internal program group 433, externalprogram reception means 434, data management means 435, and display dataoutput means 436.

[0044] The control system 431 controls the whole operation of thedigital camera 100, for example, an aperture motor drive section (notshown) in the optical system, the operation of the signal processingsection 3, the frame memory 6, the signal processing section 7, and therecording medium control section 8, and execution of the input commanddetermination means 432 to the display data output means 436.

[0045] When the user selects desired operation or processing byoperating a switch, etc., disposed on the digital camera 100, the inputcommand determination means 432 determines a digital signal output fromthe input means 5 and determines what the user-entered command operationis. According to the determination result, the input commanddetermination means 432 transfers control to the corresponding programin the internal program group 433 or transfers control to the controlsystem 431 for the external program reception means 434 to receive anexternal program.

[0046] The internal program group 433 consists of programs forcontrolling storage of picked-up image data in the recording medium 9,read or write of data from or into the expanded recording medium 10, LEDdisplay at the image picking up time, etc.,; the programs are containedin the ROM 43 as basic processing programs. For example, the internalprograms include a JPEG compression program required for writing imagedata into the recording medium 9.

[0047] The external program reception means 434 is started when theinput command determination means 432 outputs an external programintroduction command.

[0048] The external program reception means 434 determines which of thePC or the like, the expanded recording medium 10, and the communicationline a program is to be introduced from by the contents of the externalprogram introduction command and performs corresponding receptionprocessing, then transfers control to the data management means 435.

[0049] When picked-up image data is written into the recording medium 9,deleted, or added or program code introduced from the outside iswritten, deleted, or added, the data management means 435 performs datamanagement equivalent to file management widely performed in a computersuch as the PC.

[0050] The image data (data compressed in JPEG) and thumbnail image dataare processed by the internal program 433 or its equivalent circuit andare written into the recording medium 9 by the recording medium controlsection 8.

[0051] The display data output means 436 outputs LED display data, imagedata, or display data of a menu, etc., to the LED display means 15 orthe liquid crystal display 16 of the digital camera 100.

[0052]FIG. 3 is a block diagram to show a configuration example of imageselection means 45.

[0053] Image selection means 45A shown in FIG. 3a comprises print imageselection means 453 for displaying picked-up image data on the liquidcrystal display 16 in order for the user to select a desired print imageand output method specification means 454 for specifying printspecifications of the number of print sheets, print paper size, printcolor mode (full color, single color, monochrome), etc., and an externalsystem to which the image data is to be transmitted. (See firstembodiment.)

[0054] Image selection means 45B shown in FIG. 3b comprises thumbnailimage display means 452 for displaying thumbnail image data on theliquid crystal display 16 in a fast forward manner, print imageselection means 453′ for requesting the user to select a desired imagefrom among displayed thumbnail images and displaying the image datacorresponding to the user-selected thumbnail image for the user torecognize it, and output method specification means 454 for specifyingprint specifications and an external system to which the image data isto be transmitted. (See second embodiment.)

[0055] Image selection means 45C shown in FIG. 3c comprises thumbnailimage print means 452′ for adding index code to thumbnail image data andtransmitting to a printer for printing thumbnail images, print imageselection means 453″ for displaying a thumbnail image selection screenon the liquid crystal display 16 for the user to specify a desired imagebased on the printed thumbnail images and displaying the specified imagedata for the user to recognize it, and output method specification means454 for specifying print specifications and an external system to whichthe image data is to be transmitted. (See third embodiment.) Imageselection means 45D shown in FIG. 3d comprises additional imageselection method specification means 451 for the user to select eitherthe image selection means 45B or 45C.

[0056] The image selection means 45A, 45B, 45C, or 45D may be introducedfrom the outside or can also be stored in the ROM 43 as one of theinternal programs 433 making up the control means 430 (FIG. 2). Theoutput method specification means 454 has a setup value registrationtable comprising setup values and image index numbers provided in aone-to-one correspondence with each other.

[0057]FIG. 4 is a schematic representation to execute a direct printfunction for transmitting print image data to a printer, showing therelationship among the image selection means 45, the print image datapreparation program group 50, and the control means 430. FIG. 5 is aflowchart to show the operation of the control section 4 when the directprint function is executed.

[0058] In FIG. 4 and FIG. 5, when the user turns on an image selectionprocessing switch, the input command determination means 432 gives codemeaning image selection to the control system 431, which then reads theimage selection means (program) 45 from the ROM 43 or the recordingmedium 9 through the recording medium control section 8 at step P1.

[0059] When the image selection means 45 is expanded in the RAM 42, thecontrol system 431 transfers control to the image selection means 45.When the user selects a desired image and specifies a desired outputmethod, the image selection means 45 goes to step P3 if the externalsystem to which image data is to be transmitted is the printer 240 or afacsimile machine. If the external system is the PC 200 or image data issent to the communication line through the modem 150, the imageselection means 45 goes to step P5 and transfers control to the controlsystem 431 (P2).

[0060] The control system 431 gives an instruction for reading the printimage data preparation program group 50 stored in the ROM 43 or therecording medium 9 through the recording medium control section 8. Theprograms (51, 52, 531, 532, 533, 54) in the print image data preparationprogram group 50 are read in the instruction order of the control system431 and are expanded in the RAM 42 at step P3.

[0061] The control system 431 transfers control to the programs in theprint image data preparation program group 50 in order for preparingprint image data. At the termination of preparing the print image dataat step P4, control goes to step P5. The 1-frame image data can also bedivided into several blocks in the subscanning direction for preparingthe print image data.

[0062] If the specified external system is the printer 240, the imagedata transmission means 54 transmits print image data and print controldata via the interface 11 to the printer 240. If the specified externalsystem is a facsimile machine, the image data transmission means 54transmits monochrome print image data. If the external system is the PC200 or image data is sent to the communication line through the modem150, the image data transmission means 54 transmits image data or printimage data and print control data at step P5.

[0063] UV components of the image data (YUV component data) transferredto the print image data preparation program group 50 are set to U=u andV=v (−1<u<1 and −1<v<1), whereby the image data output from the printimage data preparation program group 50 can be made single-color (forexample, sepia, blue, or green) image data. U=0 and V=0 are set, wherebythe image data output from the print image data preparation programgroup 50 can be made monochrome image data.

[0064] The print image data preparation program group 50 contains a datadecompression program 51 for decompressing compressed data read from therecording medium 9, an RGB conversion program 52 for converting imagedata consisting of YUV components into RGB components, a printer driver53, and image data transmission program 54 for transmitting print data.

[0065] The printer driver 53 has the same configuration as a printerdriver for preparing print data in PC, etc., and comprises three modulesof rasterizer, color correction, and halftone to provide binary data.

[0066] Preferably, a color conversion parameter is added to the RGBconversion program 52 and a UV value conversion routine for setting U=0and Y=0 at the preceding stage of RGB conversion when the colorconversion parameter is set to a given value (for example, ‘0, 0’) isadded.

[0067] The image data transmission program 54 can also be configured totransmit print image data with the digital camera 100 connected to thecommunication line through the modem connected to the interface 11.Further, it can also be configured to transmit print image data bywireless with the digital camera lob connected to a radio unit such as aportable telephone through the modem connected to the interface 11.

[0068]FIG. 6 is a block diagram to show the configuration of the outputmethod specification means 454. The output method specification means454 comprises output method specification screen display means 4541 fordisplaying an output method specification screen for specifying printspecifications and an external system to which image data is to betransmitted (FIG. 7b), number-of-print-sheets specification means 4542for specifying the number of print sheets, print size specificationmeans 4543 for specifying a print paper size, print color modespecification means 4544 for specifying a print color mode, and outputunit specification means 4545 for specifying an external system to whichimage data is to be transmitted.

[0069] Preferably, the print size specification means 4543 comprises atable in which print paper sizes, such as A4, A6, and postcard orbusiness card size, L format, and E format used with normal silver saltphotos, are previously registered.

[0070]FIG. 7 shows an example of the rear part of the digital camera100. The digital camera 100 is provided on the rear with the liquidcrystal display 16 for displaying an image or a function menu, etc.,buttons 19 and 20 for scrolling the screen of the liquid crystal display16 up and down and from side to side, and function selection buttons 17and 18. FIG. 7a provides an image display example and 7 b provides anoutput method specification screen example.

[0071] Embodiment

[0072] Embodiments of image selection means 45 (45A, 45B, 45C, 45D) willbe discussed.

[0073] First Embodiment

[0074]FIG. 8 is a flowchart to show an operation example of imageselection means 45A. In the operation example, photographed image datapieces are displayed in order on a liquid crystal display and the useris requested to select a desired print image and specify printspecifications of the number of print sheets, print paper size, printcolor mode (color, single color, or monochrome), etc., then print imagedata is prepared and transmitted to an external system.

[0075] When the image selection means 45A is transferred to a RAM 42, acontrol system 431 transfers control to the image selection means 45A.Print image selection means 453 reads 1-frame image data, transfers theimage data to a frame memory 6, uses a data decompression program todecompose JPEG image data, and displays a candidate image 31 on a liquidcrystal display 16 at step S1. In this case, an index number is added tothe candidate image on the display.

[0076] If the user continues to press a button 19, the print imageselection means 453 displays candidate images in order. When the userreleases the button, the print image selection means 453 stops thedisplay at the current image. If the user continues to press a button20, the print image selection means 453 displays the preceding candidateimages in order. When the user releases the button, the print imageselection means 453 stops the display at the current candidate image atstep S2.

[0077] If the user presses either the button 17 or 18, the print imageselection means 453 assumes the candidate image to be selected andtransfers control to output method specification means 454 at step S3.

[0078] The output method specification means 454 displays an outputmethod specification menu as shown in FIG. 7b by output methodspecification screen display means 4541, prompting the user to select orenter the print specifications and the external system to which imagedata is to be transmitted.

[0079] At this time, initial display is, for example, “number of printsheets=1, print paper size=A4, print color mode=full color, outputunit=color printer.” The inside of a box 21 that can be specified orselected is displayed in a color different from the colors of otherboxes at step S4.

[0080] First, when the user presses the button 17 or 18,number-of-print-sheets specification means 4542 goes to a step forspecifying the number of print sheets. Each time the user presses abutton 19, the number of print sheets is incremented by one starting atthe initial value and the resultant number of sheets is displayed. Eachtime the user presses a button 20, the number of print sheets displayedis decremented by one. If the user presses either the button 17 or 18,the current display value is set as the number of print sheets and isstored in the location corresponding to the image index number in asetup value registration table at step S5 and control goes to the nextstep.

[0081] When the user presses the button 17 or 18, print sizespecification means 4543 goes to a step for selecting a print paper sizeand displays the contents of a print size registration table in whichprint paper sizes are previously registered. If the user presses thebutton 19 or 20 to select a desired print paper size and presses thebutton 17 or 18, the selected print paper size is set and is stored inthe location corresponding to the image index number in the setup valueregistration table at step S6 and control goes to the next step.

[0082] When the user presses the button 17 or 18, print color modespecification means 4544 goes to a step for selecting a print color modeand displays the contents of a print color mode registration table inwhich print color modes are previously registered. If the user pressesthe button 19 or 20 to select a desired print color mode and presses thebutton 17 or 18, the selected print color mode is set. If full color isselected as the print color mode, a print color mode parameter in an RGBconversion program 52 is set to 1. If a single color is selected as theprint color mode, the print color mode parameter in the RGB conversionprogram 52 is set to 2. If monochrome is selected as the print colormode, the print color mode parameter in the RGB conversion program 52 isset to 3. The print color mode parameter is stored in the locationcorresponding to the image index number in the setup value registrationtable at step S7.

[0083] When the user presses the button 17 or 18, output unitspecification means 4545 goes to a step for selecting an output unit anddisplays the contents of an output unit registration table in whichoutput units are previously registered. If the user selects a colorprinter as the output unit, an output unit parameter in an image datatransmission program 54 is set to 1. If the user selects a facsimile asthe output unit, the output unit parameter in the image datatransmission program 54 is set to 2. If the user selects a PC as theoutput unit, the output unit parameter in the image data transmissionprogram 54 is set to 3. If the user selects a communication terminal asthe output unit, the output unit parameter in the image datatransmission program 54 is set to 4. If the user presses the button 17or 18, the selected output unit is set and the setup value correspondingto the selected output unit is stored in the location corresponding tothe image index number in the setup value registration table, thencontrol returns to step S1 to display another candidate image. Ifanother candidate image does not exist, the output unit parameter valueis checked. If the value is 1 or 2, control goes to step S9; if thevalue is 3 or 4, control goes to step S16.

[0084] The control system 431 expands programs contained in a printimage data preparation program group 50 in the RAM 42 in order andtransfers control to a compressed data decompression program 51 at stepS9.

[0085] The compressed data decompression program 51 reads image data(JPEG image data) selected by the print image selection means 453 intothe RAM 42 and decompresses the data at step S10.

[0086] At the termination of decompressing the compressed image data,the RGB conversion program 52 checks the print color mode parameter atstep S11. If the print color mode parameter has a value of 1, controlgoes to step S12. If the print color mode parameter has a value of 2,all UV components of the image data are converted into U=u and V=v. Ifthe print color mode parameter has a value of 3, all UV components ofthe image data are converted into U=0 and V=O.

[0087] The RGB conversion program 52 converts the image data consistingof YUV components into image data consisting of R (red), G (green), andB (blue) components at step S12. When the UV components are U=u and V=v,the image data is converted into single-color image data. When the UVcomponents are U=0 and V=0, the image data is converted into monochromeimage data.

[0088] A rasterizer 531 converts the image data into RGB continuous-tone(for example, 256-gray-level) bit image data undergoing rasterconversion for each of R, G, and B at step S13.

[0089] A color correction module 532 applies color correction processingto the RGB continuous-tone bit image data to relate the data to printcolors and converts the data into CMYK continuous-tone bit image datafor K (black), C (cyan), M (magenta), and Y (yellow) printing at stepS14.

[0090] A halftone module 533 uses a dither method or an error diffusionmethod to perform halftone processing for the CMYK continuous-tone bitimage data at step S15, whereby a bit map binarized for each color(binary data table) is prepared.

[0091] At the termination of the halftone processing, the image datatransmission program 54 checks the print color mode parameter. If thevalue of the print color mode parameter is 1, the image datatransmission program 54 transmits the setup values of the number ofprint sheets and the print paper size, a print control signal, andbinary bit map data to a color ink jet printer 240, for example, throughan interface 11 at step S16. The color ink jet printer 240 can receivethe print control signal and print data directly from the digital camera100 and print a desired number of sheets of the photographed image onrecording paper of a desired size.

[0092] If the user specifies a single color or monochrome as the printcolor mode, the image is printed in the single color or monochrome if itis color-photographed. If the value of the print color mode parameter is2, the image data transmission program 54 transmits the setup values ofthe number of print sheets and the print paper size, a print controlsignal, and binary bit map data to a facsimile through an interface 11.If the value of the print color mode parameter is 3 or 4, the image datatransmission program 54 transmits JPEG image data or the setup values ofthe number of print sheets and the print paper size, a print controlsignal, and binary bit map data to PC 200 through the interface 11 or aterminal connected to a communication line 160 through a modem 150.

[0093] Second Embodiment

[0094]FIG. 9 is a flowchart to show an operation example of imageselection means 45B (FIG. 3B) wherein thumbnail images are displayed andthe user selects a desired image and specifies print specifications ofthe number of print sheets, print paper size, print color mode, etc.,and an output unit to which image data is to be transmitted.

[0095] When the image selection means 45B is transferred to a RAM 42, acontrol system 431 transfers control to the image selection means 45B.Thumbnail image display means 452 reads all thumbnail image data andexpands the data in the RAM 42 at step S21.

[0096] The thumbnail image display means 452 uses a data decompressionprogram to decompose the thumbnail image data, enlarges the image data,adds an index number to the enlarged thumbnail image data, and displaysthe thumbnail image on a liquid crystal display 16 at step S22. A numberof thumbnail images may be displayed on the liquid crystal display 16without enlarging the thumbnail image data.

[0097] Each time the user presses a button 19, print image selectionmeans 453′ displays one enlarged thumbnail image. If the user stopspressing the button 19, the print image selection means 453′ continuesto display the current thumbnail image. Each time the user presses abutton 20, the print image selection means 453′ displays the precedingthumbnail image. If the user stops pressing the button 20, the printimage selection means 453′ continues to display the current thumbnailimage at step S23.

[0098] If the user stops pressing the button 19 or 20 and presses eitherthe button 17 or 18 with the thumbnail image displayed, the print imageselection means 453′ assumes the image to be selected. When the userselects images from among the thumbnail images and completes selectionof desired images, the print image selection means 453′ transferscontrol to the control system 431.

[0099] The control system 431 transfers control to output methodspecification means 454. At step S25, the output method specificationmeans 454 handles output method specification processing of printspecifications, an output unit to which image data is to be transmitted,etc., and checks the value of an output unit parameter at step S25. Ifthe parameter value is 1 or 2, control goes to step S26; if theparameter value 3 or 4, control goes to step S27.

[0100] The control system 431 expands print image data and programscontained in a print image data preparation program group 50 in the RAM42 in order and transfers control to the print image data preparationprogram group 50 at step S26.

[0101] The print image data preparation program group 50 performssimilar processing to steps S10 to S15 in FIG. 8, namely, performsdecompression processing of image data (JPEG image data) selected by theprint image selection means 453′, RGB conversion processing,rasterizing, color correction processing, and halftone processing atstep S27.

[0102] At the termination of the halftone processing, as at step S16 inFIG. 8, an image data transmission program 54 checks the output unitparameter and transmits the print image data or JPEG image data to thespecified output unit at step S28.

[0103] Third Embodiment

[0104]FIG. 10 is a flowchart to show an operation example of imageselection means 45C (FIG. 3c) wherein thumbnail image data is printed ata printer and the user selects a desired image from among the printedthumbnail images and specifies print specifications of the number ofprint sheets, print paper size, print color mode, etc., and an outputunit to which image data is to be transmitted.

[0105] A control system 431 expands programs contained in a print imagedata preparation program group 50 in a RAM 42 in order and transferscontrol to the image selection means 45C at step S31.

[0106] Thumbnail image print means 452′ reads all thumbnail image data,expands the image data in the RAM 42, decompresses the thumbnail imagedata in the RAM 42, and adds an index number to each thumbnail imagedata piece at step S32.

[0107] As described at steps S12 to S15 in FIG. 8, the print image datapreparation program group 50 performs RGB conversion processing,rasterize processing, color correction processing, and halftoneprocessing to prepare print thumbnail image data and transmits the imagedata to a printer 240 at step S33. In this case, the thumbnail imageprint means 452′ may set U and V components of the thumbnail image datain the RAM 42 to U=0 and V=0 to print a monochrome thumbnail image atthe printer 240.

[0108] Thumbnail images each with an index number are printed at theprinter 240 at step S34.

[0109] Print image selection means 453′ displays a message on a liquidcrystal display, prompting the user to select a desired image from amongthe printed thumbnail images and enter the index number of the selectedimage at step S35.

[0110] If the user presses a button 19 as many times as the number ofdigits of the index number of the desired image and then presses abutton 17 or 18, the print image selection means 453″ reads the imagedata corresponding to the index number from a recording medium 9 into aframe memory 6 and displays the image on a liquid crystal display 16 atstep S36.

[0111] If the user furthermore presses the button 17 or 18, the printimage selection means 453″ assumes the image to be selected andtransfers control to output method specification means 454 at step S37.

[0112] The output method specification means 454 handles setting ofprint specifications and specification of an output unit to which imagedata is to be transmitted at step S38 as at steps S4 to S8 in FIG. 8. Toselect another candidate image, control returns to step S35. If anothercandidate image does not exist, the value of an output unit parameter ischecked. If the parameter value is 1 or 2, control goes to step S39; ifthe parameter value is 3 or 4, control goes to step S40.

[0113] The print image data preparation program group 50 performsdecompression processing of selected image data (JPEG image data), RGBconversion processing, rasterize processing, color correctionprocessing, and halftone processing at step S39 as at steps S10 to S15in FIG. 8.

[0114] At the termination of the halftone processing, as at step S16 inFIG. 8, an image data transmission program 54 checks the output unitparameter and transmits the print image data or JPEG image data to thespecified output unit at step, S40.

[0115] It is understood that the foregoing description is preferredembodiments of the invention and that various changes and modificationsmay be made in the invention without departing from the spirit and scopethereof.

[0116] As described above, according to the invention, images aredisplayed on display means such as a liquid crystal display of thedigital camera and the user selects a desired image from among thedisplayed images and specifies the print specifications of the number ofprint sheets, a print paper size, a print color mode, etc., then cantransmit the print image data prepared based on the user's selection andspecification from the digital camera to a printer. Therefore, aphotographed image can be printed without intervention of anotherprocessing system such as a PC and it can be expected that digitalcameras will come into wider use for those who do not have a PC, etc.,or who have a PC, but are unfamiliar with handling the PC.

In the claims:
 1. A digital camera, comprising: an image conversiondevice that converts a plurality of images into signals; a recordingmedium that stores image data corresponding to the signals; a displaythat displays at least one displayed image based on at least some of thestored image data; and an input device, wherein the at least onedisplayed image is selected to determine output image data when a userinputs a first command via the input device, wherein the input of thefirst command causes the display to automatically display an outputspecification menu after the first command is input, and wherein theuser can select at least one predetermined output specification from theoutput specification menu via the input device.
 2. The digital cameraaccording to claim 1, wherein an external device processes the outputimage data based on the at least one predetermined output specification.3. The digital camera according to claim 2, wherein the digital cameradirectly outputs the output image data to the external device.
 4. Thedigital camera according to claim 1, wherein the first command is aselection command for selecting the at least one displayed imagedisplayed on the display as at least one selected image.
 5. The digitalcamera according to claim 4, wherein the at least one displayed imagecomprises at least one thumbnail image.
 6. The digital camera accordingto claim 5, wherein the at least one thumbnail image is displayed on thedisplay based on thumbnail image data stored in the recording medium tobe associated with the stored image data.
 7. The digital cameraaccording to claim 5, wherein two or more of the at least one thumbnailimage are sequentially displayed on the display before the user inputsthe first command.
 8. The digital camera according to claim 5, whereintwo or more of the at least one thumbnail image are simultaneouslydisplayed on the display before the user inputs the first command. 9.The digital camera of claim 4, wherein the user changes the at least onepredetermined output specification by inputting a second command via theinput device.
 10. The digital camera of claim 9, wherein the inputdevice comprises a scroll button, and wherein the user inputs the secondcommand by depressing the scroll button.
 11. The digital cameraaccording to claim 9, wherein the at least one predetermined outputspecification includes at least one of a number of print sheets and aprint paper size.
 12. The digital camera according to claim 1, wherein,when the output specification menu is initially displayed, at least oneinitial output specification value for the at least one predeterminedoutput specification is displayed on the output specification menu. 13.The digital camera according to claim 12, wherein the at least oneinitial output specification value includes an initial value for atleast one of the number of print sheets and the paper size.
 14. Thedigital camera according to claim 1, wherein the input device comprisesat least one scroll button.
 15. The digital camera according to claim14, wherein the at least one scroll button allows a user to change theat least one displayed image displayed on the display.
 16. The digitalcamera according to claim 14, wherein the at least one scroll buttonallows a user to change at least one output specification contained inthe output specification menu to select the at least one predeterminedoutput specification.
 17. The digital camera according to claim 15,wherein the at least one scroll button allows the user to change atleast one output specification contained in the output specificationmenu to select the at least one predetermined output specification. 18.The digital camera according to claim 15, wherein the input devicefurther comprises at least one function button, wherein the at least onefunction button allows the user to select a displayed image displayed onthe display.
 19. The digital camera according to claim 16, wherein theinput device further comprises at least one function button, wherein theat least one function button allows the user to select at least oneoutput specification contained in the output specification menu as theat least one predetermined output specification.
 20. The digital cameraaccording to claim 17, wherein the input device further comprises atleast one function button, wherein the at least one function buttonallows the user to select at least one output specification contained inthe output specification menu as the at least one predetermined outputspecification, and wherein the at least one function button allows theuser to select a displayed image displayed on the display.
 21. Thedigital camera according to claim 1, wherein the input device includes afunction button, wherein the user inputs the first command by depressingthe function button under a first predetermined condition.
 22. Thedigital camera according to claim 21, wherein the first predeterminedcondition includes a condition in which a desired image is currentlydisplayed on the display as the at least one displayed image.
 23. Thedigital camera according to claim 22, wherein the input device includesa scroll button, wherein the user can change the at least one displayedimage displayed on the display by inputting a second command via thescroll button before the first command is input.
 24. The digital cameraaccording to claim 23, wherein, when the output specification menu isinitially displayed, at least one initial output specification value forthe at least one predetermined output specification is displayed on theoutput specification menu, wherein the at least one initial outputspecification value displayed on the output specification menu ischanged only when the user inputs a third command via the scroll button.25. The digital camera according to claim 22, wherein the user sets atleast one output specification value, which is currently displayed onthe output specification menu, as the at least one predetermined outputspecification by inputting a command via the function button.
 26. Thedigital camera according to claim 24, wherein the user sets at least oneoutput specification value, which is currently displayed on the outputspecification menu, as the at least one predetermined outputspecification by inputting a command via the function button.
 27. Thedigital camera according to claim 1, wherein the at least onepredetermined output specification includes at least one of a number ofsheets and a paper size.
 28. The digital camera according to claim 1,wherein the at least one predetermined specification includes dataindicative of an external device to which the user desires to the outputimage data from the digital camera and that is selected by a user fromavailable external devices including at least two of a printer, afacsimile, a PC and a communication terminal.
 29. The digital cameraaccording to claim 28, wherein the communication terminal includes awireless telephone.
 30. The digital camera according to claim 1, furthercomprising conversion software contained in the digital camera, whereinthe conversion software formats the output image data to be output fromthe digital camera to an external device.
 31. The digital cameraaccording to claim 30, wherein the conversion software is supplied tothe digital camera from an external source and is installed in a memorycontained within the digital camera.
 32. The digital camera according toclaim 30, wherein the conversion software comprises a printer driver,and wherein the printer driver comprises at least one of a rasterizermodule, a half tone module, and a color correction module.
 33. Thedigital camera according to claim 1, wherein conversion software formatsthe output image data based on the at least one predetermined outputspecification.
 34. The digital camera according to claim 33, wherein theconversion software comprises a printer driver, and wherein the printerdriver comprises at least one of a rasterizer module, a half tonemodule, and a color correction module.
 35. The digital camera accordingto claim 1, wherein the digital camera comprises a wireless transmitterthat transmits the output image data to an external device by wirelesstransmission.
 36. The digital camera according to claim 35, wherein theexternal device is a wireless telephone.
 37. The digital cameraaccording to claim 1, wherein the stored image data includes higherresolution image data.
 38. The digital camera according to claim 37,wherein the stored image data further includes lower resolution imagedata associated with the higher resolution image data.
 39. The digitalcamera according to claim 38, wherein the lower resolution image dataincludes thumbnail image data.
 40. The digital camera according to claim37, wherein the at least one displayed image is displayed on the displaybased on the higher resolution image data.
 41. The digital cameraaccording to claim 39, wherein the at least one displayed image isdisplayed based on the thumbnail image data.
 42. The digital cameraaccording to claim 41, wherein the at least one displayed image isdisplayed based on the thumbnail image data by enlargement.
 43. Thedigital camera according to claim 37, wherein the output image dataincludes the higher resolution image data.
 44. The digital cameraaccording to claim 37, wherein the output image data includes dataobtained based on the higher resolution image data.
 45. The digitalcamera according to claim 39, wherein the output image data includes thethumbnail image data.
 46. The digital camera according to any one ofclaims 43 to 45, wherein the output image data further includes dataindicative of the at least one predetermined output specificationselected by the user.
 47. A digital camera, comprising: an imageconversion device that converts a plurality of images into signals; arecording medium that stores image data corresponding to the signals; adisplay that displays at least one displayed image based on at leastsome of the stored image data; and an input device having first andsecond buttons, wherein two or more of the at least one displayed imageare sequentially displayed on the display when the first button iscontinuously depressed; wherein an output specification menu for acurrently displayed one of the at least one displayed image is displayedon the display when the second button is depressed.
 48. The digitalcamera according to claim 47, wherein the currently displayed one of theat least one displayed image is selected to determine output image datawhen the second button is depressed.
 49. The digital camera according toclaim 47, wherein a user can select at least one predetermined outputspecification from the output specification menu.
 50. The digital cameraaccording to claim 49, wherein the at least one predetermined outputspecification includes a number of copies.
 51. The digital cameraaccording to claim 49, wherein the first button is used to change adisplayed value of an output specification in the output specificationmenu, and the second button is used to set a currently displayed valueof the output specification in the output specification menu as the atleast one predetermined output specification.
 52. A digital camera,comprising: an image conversion device that converts a plurality ofimages into signals; a recording medium that stores image datacorresponding to the signals; a display that displays at least onedisplayed image based on at least some of the stored image data; and aninput device, wherein an output specification menu for the at least onedisplayed image is displayed on the display via the input device,wherein a user can select at least one predetermined outputspecification from the output specification menu via the input device,and wherein the at least one predetermined output specification includesa number of copies.
 53. The digital camera according to claim 52,wherein the input device has first and second buttons, wherein the firstbutton is used to change a displayed value for the number of copies inthe output specification menu, and the second button is used to set acurrently displayed value for the number of copies in the outputspecification menu as the at least one predetermined outputspecification.
 54. A method of outputting image data from a digitalcamera including a display and an input device, the method comprising:converting a plurality of images into signals; storing image datacorresponding to the signals; displaying at least one displayed image onthe display based on at least some of the stored image data; selectingthe at least one displayed image to determine output image data when afirst command is input via the input device; automatically displaying anoutput specification menu in response the first command; and selectingat least one predetermined output specification from the outputspecification menu via the input device.
 55. A method of outputtingimage data from a digital camera including a display and an input devicehaving first and second buttons, the method comprising: converting aplurality of images into signals; storing image data corresponding tothe signals; displaying at least one displayed image on the displaybased on at least some of the stored image data; sequentially displayingtwo or more of the at least one displayed image on the display when thefirst button is continuously depressed; and displaying an outputspecification menu for a currently displayed one of the at least onedisplayed image on the display when the second button is depressed. 56.A method of outputting image data from a digital camera including adisplay and an input device, the method comprising: converting aplurality of images into signals; storing image data corresponding tothe signals; displaying at least one displayed image on the displaybased on at least some of the stored image data; displaying an outputspecification menu for the at least one displayed image on the displayvia the input device; and selecting at least one predetermined outputspecification from the output specification menu via the input device,wherein the at least one predetermined output specification includes anumber of copies.